Thermoplastic resins, which are represented by styrene-based resins, are used as materials for vehicle interior components such as switches for car air-conditioners and car audio systems. It is well known that in a case in which molded articles produced using thermoplastic resins are assembled, interlocking parts of the molded articles or parts that are brought into contact with (rubbed with) components formed from materials of different kinds or materials of the same kind produce creaking sound, and that components wear away after being used for a long time.
In order to solve such problems, application of grease on the interlocking parts or contact parts of resin surfaces is implemented. However, since this application of grease requires time and expenses for operation, it is not economically efficient, and there are limitations on the sustenance of effects. Thus, for the purpose of promoting improvements in the sliding characteristics and the friction and abrasion characteristics of thermoplastic resins, Patent Literature 1 suggests a thermoplastic resin composition having a polyethylene having a particular molecular weight distribution blended therein. Furthermore, Patent Literature 2 suggests a thermoplastic resin composition in which a polyethylene having a particular density or molecular weight and a copolymer formed from a vinyl monomer are proportionally mixed.